Transformer for electric-arc cutting and welding apparatus



Nov. 29, 1927. F. c. OWEN v TRANSFORMER FOR ELECTRIC ARC CUTTING AND WELDING APPARATUS Filed Nov.

UNI-TED STATES FREDERICK Ge OWEN, OF FAYETTEVILLE, NORTH CAROLINA.

TRANSFORMER FO R, ELECTRIC-ARC CUTTING AND WELDING- APPARATUS.

Application filed November This invention relates to alternating cur rent electric are cutting and welding apparatus and more particularly to polyphase transformers for such apparatus. I

The invention has for one of its objects to improve and simplify the general con struction of transformers of the character stated and to provide transformers that shall be so wound and constructed as to obviate the necessity of the use of fans or other mechanical cooling means and the use of flux diverters, damping ,devices or manually operated resistances and reactances for regulating the current and potential in the primary and secondary windings.

With the foregoing and other objects in view, the invention consists of the novel construction, combination and arrangement of parts hereinafter fully described and claimed, and illustrated in the accompany mg drawing, wherein: Figure 1 is a diagrammatic View of an alternating current electric are cutting and welding apparatus embodying a transformer constructed in accordance with my inven tion Figure 2 is a similar view illustrating a slightly modified form of the transformer, and

Figures 3 and l are similar vi-ews illustrating further modified forms of the transformer.

Corresponding and like parts are referred to in the following description, and designated in all the figures of the drawing, by similar reference characters.

Referring in detail to the drawing, and more particularly to Figure 1, 1 designates a core which is of laminated construction and embodies a top leg-2, bottom leg 3, side legs 1-, and middle leg 5. r

The primary winding of the transformer comprises a section consisting of coils 6, 7 and 8 connected in seriesand mounted on the legs 2, 3 and 4 at one side of the leg 5, a section consisting of coils 9. 10 and 11 connected in series and mounted on the legs 2, 3

and 4 at the opposite side of the leg 5, and a section consisting of a coil 12 mounted on the leg 5. Those sections of the primary winding located at opposite sides of the leg 15 are connected by a wire 13, and these sections and the section mounted on the leg 5 are connected by said wire and av wlre 14. Leads 15, 16 and 17 connected respectwely to the respectivesections of the primary winding 12, 1925. Serial No. 68,608.

extend tothe power circuit. The sections of the primary'winding are, as should be apparent, Y-connected.

The secondary winding of the transformer comprises a single coil 18 mounted on the leg 5 and provided with taps 19-. One end of the coil 18 is connected by a lead 20 to the work 21 which is to be cut, welded or on thelegs 2 and 3 at one side of the leg 5,-

a section consisting of main or voltage regulating coils 26 and 27 mounted on the legs 2 and 3 at the opposite side of the leg5, and a section consisting of an auxiliary or current regulatingcoil 28 mounted on the leg 5. These coils are connected in series, and the coil 28 is provided with taps 29. A lead 20 extends from the coil 27 to the work 21, and any one of the taps 29 is adapted to be connected to the electrode 23 by a'lead 22.

A further modified form of the transformer is shown in Figure 3. This transformer embodies a core and primary winding similar to the corresponding parts of the transformers shown in Figures 1 and 2. The secondary winding of this transformer differs from the secondary windings of said other transformers, and comprises a section consisting of main or voltage regulating coils 30 and 31 mounted on the legs 2 and 3 at one side of the leg 5, a section consisting of main or voltage regulating coils 32 and 33 mounted on the legs 2 and 3 at the opposite side of the leg 5, and a section consisting of an auxiliary or current regulating coil 34: mounted on the leg 5. The respective sections of the mainor voltage regulatin coils 30-33 are connected in parallel, and these sections are connected in series with the auxiliary or current regulating coil 34. The coils are connected by a lead 20 to the work 21; The coil 34 is provided with taps 35 any one of which isadapted to be connected to the electrode 23 by a lead 22 r The transformer shown in Figure 4 dif fers from the other transformers in that it 1 electrode.

has two independent secondary windings each of which consists'of coils 36. 37 and 38 and are mounted on the legs 2, 3 and 4 at opposite sides of the leg 5. Any one or two of the coils of each of these windings may be used as the main or voltage regulating coil or coils, and such coil or coils will be connected to the work. The remaining coil or coils of each of these windings will constitut-e the auxiliary or current regulating coil or coils and will be provided with taps any one of which may be connected to the The coils of each of these windings are connected in series.

In each transformer. the core provides a plurality of completely closed magnetic paths, the primary winding has a section distributed around the greater portion of each of said paths and a section distributed around a portion of both saidpaths, and the secondary winding is distributed about both of said paths. W hen current flows through the primary winding a constant main voltage and a variable secondary voltage will be induced in the secondary winding. The reaction between these voltages is such that there is induced in the secondary circuit including the work and electrode, a light current at light load and a heavy current at heavy load, with the result that a stable arc oi": high power factor may be readily maintained during overhead, vertical and horizontal cutting, welding or repairing of steel, wrought iron, cast iron, malleable iron, aluminum, brass, bronze, copper and alloy metals. -Eurthermore, the arc is tree from sputtering or spitting, and it has been found that a skilled operator can maintain an are within one and one-half per cent plus or minus of the rated capacity of the tap with which the electrode is connected.

What is claimed is 1. A transformer comprising a core providing a plurality of closed magnetic paths, a primary winding embodying sections each distributed around the greater portion of each of said paths and a section distributed around a portion of both of said paths, and a secondary winding distributed around a plurality of said paths.

2. A transformer comprising a core providing a plurality of closed magnetic paths, a primary winding embodying sections each distributed around the greater portion of each of said paths and a section distributed around a portion of both of said paths, and a. secondary winding embodying coils disicensee tributed around difi'erent portions of said paths.

3. A transformer comprising a core having top, bottom. side and middle legs, a primary winding comprising similar sections distributed around said top, bottom and side legs at opposite sides of said middle leg, and a section distributed around the middle leg, and a secondary winding distributed around the middle leg.

4. A transformer comprising a core having top, bottom, side and middle legs, a primary winding comprising similar sections distributed around the top, bottom and side legs at opposite sides of the middle le and a section distributed around the midd e leg, and a secondary winding having coils distributed about the top and bottom legs at opposite sides of the middle leg.

5. A transformer comprising a core having top, bottom, side and middle legs, a primary winding comprising similar sections distributed'around the top, bottom and side legs at opposite sides of the middle leg, and a section distributed around the middle leg, and a secondary winding distributed around the top, bottom and middle legs.

6. A transformer comprising a core having top. bottom, side and middle legs, a 'primary winding comprising similar sections distributed around the top, bottom and side legs at opposite sides of the middle leg, and a section distributed around the middle leg, and a secondary winding embodying coils distributed around the top and bottom legs and connected in parallel and a coil distributed around the middle leg and connected in series with said other coils.

7. A transformer comprising a core havingtop, bottom, side and middle legs, a primary winding comprising similar sections distributed around the top, bottom and side legs at opposite sides of the middle leg, and a section distributed around the middle leg, and secondary windings distributed 

